SEPIC converter nearly doubles frequency performance

September 10, 2012 //
By Christoph Hammerschmidt

Power devices supplier ON Semiconductor has released an adjustable output non-synchronous single-ended primary-inductor converter (SEPIC)/ boost controller, targeted for use in automotive applications. With a fixed switching frequency of 2 megahertz (MHz), the NCV898031 almost doubles the frequency performance offered by most competing devices on the market.

Covering a wide input voltage range of 3.2 V to 40 V, the controller uses peak current mode control with internal slope compensation. It has a built-in regulator that supplies charge to the gate driver, plus a 1.2 V ±2% reference voltage. Protection features include internally-set soft-start, under-voltage lockout, cycle-by-cycle current limiting and thermal shutdown. The AEC-qualified NCV898031 can cope with a 45 V load dump and has an operational temperature range of −40 °C to 150 °C. In addition, its low sleep-mode current of typically 10 microamperes (µA) helps to keep the total ignition off quiescent current budget to a minimum.

The higher frequency operation of this device allows it to be used with smaller and lower cost inductors and output capacitors, thereby lowering the overall cost and taking up less PCB real estate. Thanks to its protection mechanisms and wide voltage range, it is highly optimized for use in automotive applications, such as instrumentation clusters and infotainment systems.

According to ON Semiconductor, the enhanced frequency performance exhibited by the NCV898031 will be of benefit to design engineers as they look to curb costs and better utilise available space, allowing smaller, less expensive passive components to be specified. In addition, its low quiescent current level will help to meet the demanding ignition-off requirements now being expected within the automotive industry.

The NCV898031 is supplied in a RoHS-compliant SOIC-8 package and is priced at $1.02 USD for 2500 unit quantities.